How to Have Fun Like Monkeys, Whales and Foxes

If you want to know how song changes the shape of a finch's brain, science can help. If you want to know how learning a song alters genetic patterns, affects mate choice and ultimately influences populations, you can learn that too. But what if you want to know how a singing bird feels?

That, it turns out, is a scientifically uncertain and even controversial question. It's difficult to study animal emotions with formal rigor, and the notion that animals might have rich inner lives was disregarded for much of the 20th century. From the behaviorist perspective pioneered by psychologists like Ivan Pavlov and B.F. Skinner, thinking animals had complex emotions was an unjustified assumption.

But from another perspective, it's as much an assumption to think animals don't have feelings. After all, humans are animals, too, and whether big brains and language are needed to experience happiness and sadness is unknown.

"The onus of proof to show otherwise should be on those who deny that animals have these capacities," says scholar and animal advocate Jonathan Balcombe, author of The Exultant Ark: A Pictorial Tour of Animal Pleasure. In the book, published in May by the University of California Press, Balcombe surveys a new generation of studies into animal feelings, especially animal pleasure. Accompanying the scholarship are photographs of animals seeming to enjoy themselves: hippos and flying foxes, zebrafish and sharks, parrots and polar bears, a whole animal kingdom of pleasure. (And, yes, there are kittens too.)

Balcombe talked with Wired.com and took us on a photographic tour.

Read the rest on Wired.com.